This invention relates to voice messaging techniques used in telephone systems.
Voice messaging telephone systems have grown in popularity over the years and are widely available for use by the public. For example, a visitor at a hotel now has the ability to receive an actual voice message from a calling party through the hotel's telephone system rather than through a hand written message slip from a member of the hotel staff. Another example is in the area of incoming call management systems, where a customer's telephone call is answered by a voice messaging system and the customer is guided by a series of announcements, i.e., voice prompts, to either place an order, receive an account balance, etc.
As described above, in a voice messaging telephone system, an announcement is played back to a user and either prompts a user for action or provides the user with information. The announcement itself may contain system information like time-of-day, which can be used to provide the time when a voice message was recorded to a user of the system. However, in the above examples, it is easy to gloss over an underlying assumption, which is that all the announcements are in one language only. Indeed, if only one language is supported, the design and use of a voice messaging system is simplified since, for example, the sentence structure required for any announcement is known a priori. However, if two languages are required to be supported in a voice messaging system, the complexities of dealing with announcements in different languages increases. This can easily be seen by conceptually comparing the English Language to another language like German, each language having its own rules of sentence construction. In addition, even in countries speaking similar languages, there are variations that need to be taken into account by any voice messaging system in playing back announcements. For example, in the United States, a date has the format of month/day/year, however, in England, the format is day/month/year, yet both countries use the English language.
As a result of language specific variations in sentence structure, etc., the design of any voice messaging system to provide the correct announcement typically results in an implementation that is language specific. For example, in English, the announcement "You have five new voice mail messages," identifies a set of English voice fragments that are played back end-to-end. Voice fragments are used rather than recordings of complete sentences in order to reduce the amount of voice storage in the voice messaging system. In other words, identical voice fragments that appear in different announcements can be shared as opposed to being needlessly duplicated. However, each additional language that is supported in a voice messaging system requires the use of a separate language specific announcement, which identifies the voice fragments associated for that particular language--essentially resulting in another set of announcements for each additional language. Therefore, continuing with the above example, the same message "You have five new voice mail messages," in another language, would identify a different announcement comprising a set of voice fragments, e.g., Spanish voice fragments, to be played back end to end. Consequently, a voice messaging system that supports English cannot be used to also provide Spanish language announcements without further language-specific design modifications to the existing voice messaging system, modifications that take time and incur additional expenses, and which thereby limit the multilingual capability of existing voice messaging systems in an increasingly international marketplace. Further, any change to one announcement, e.g., to change a particular sentence structure, may have to be repeated in all language versions of that announcement.